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1.
Sensors (Basel) ; 20(9)2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32365653

RESUMO

One of the common methods for measuring distance is to use a camera and image processing algorithm, such as an eye and brain. Mechanical stereo vision uses two cameras to shoot the same object and analyzes the disparity of the stereo vision. One of the most robust methods to calculate disparity is the well-known census transform, which has the problem of conversion window selection. In this paper, three methods are proposed to improve the performance of the census transform. The first one uses a low-pass band of the wavelet to reduce the computation loading and a high-pass band of the wavelet to modify the disparity. The main idea of the second method is the adaptive size selection of the conversion window by edge information. The third proposed method is to apply the adaptive window size to the previous sparse census transform. In the experiments, two indexes, percentage of bad matching pixels (PoBMP) and root mean squared (RMS), are used to evaluate the performance with the known ground truth data. According to the results, the computation required can be reduced by the multiresolution feature of the wavelet transform. The accuracy is also improved with the modified disparity processing. Compared with previous methods, the number of operation points is reduced by the proposed adaptive window size method.

2.
Probiotics Antimicrob Proteins ; 12(3): 1097-1114, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31828607

RESUMO

In this study, we describe enhanced in vitro probiotic activities of preformed biofilms versus planktonic cultures of Lactobacillus fermentum LfQi6 (LfQi6), a lactic acid bacterium (LAB) isolated from the human microbiome. These evaluations are used to help predict host in vivo probiotic benefits and therefore indicate that LfQi6 may provide significant probiotic benefits in the human host when administered as preformed biofilms rather than as planktonic cultures. Specifically, LfQi6 biofilms demonstrated improved in vitro performance versus LfQi6 planktonic cultures for host gastrointestinal survival and engraftment, strain-specific antimicrobial and anti-biofilm activity against clinically significant pathogens, concurrent promotion of beneficial gastrointestinal commensal biofilms, beneficial commensal enzyme activities, and host cellular-protective glutathione antioxidant activity. Evaluation of LfQi6 according to the European Food Safety Authority (EFSA 2007, 2012, 2015) Guidelines and Joint FAO/WHO Expert Consultation on Evaluation of Health and Nutritional Properties of Probiotics in Food Evaluation of Probiotics in Food (FAO/WHO, 2002) demonstrates strain safety. In summary, in vitro evaluation of Lact. fermentum LfQi6 demonstrates significant evidence for strain-specific probiotic characteristics and safety. Moreover, strain-specific as well as biofilm-phenotype-specific benefits demonstrated in vitro furthermore suggest that in vivo use of LfQi6 biofilm biomass may be of greater benefit to the human host than the use of standard planktonic cultures. This concept - potentiating probiotic benefits through the use of preformed commensal biofilms - is novel and may serve to further broaden the application of microbial biofilms to human health.


Assuntos
Antibiose , Limosilactobacillus fermentum , Probióticos , Biofilmes/crescimento & desenvolvimento , Células CACO-2 , Humanos , Limosilactobacillus fermentum/crescimento & desenvolvimento , Limosilactobacillus fermentum/metabolismo
3.
Neural Plast ; 2019: 8481371, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781183

RESUMO

Action observation therapy has recently attracted increasing attention; however, the mechanisms through which action observation and execution (AOE) modulate neural activity in stroke patients remain unclear. This study was aimed at investigating the effects of action observation and two types of AOE on motor cortical activations after stroke using magnetoencephalography. Twenty patients with stroke and 20 healthy controls were recruited for the collection of data on the beta oscillatory activity in the primary motor cortex (M1). All participants performed the conditions of resting, observation only, and video observation combined with execution (video AOE). Stroke patients performed one additional condition of affected hand observation combined with execution (affected hand AOE). The relative change index of beta oscillations was calculated, and nonparametric tests were used to examine the differences in conditions. In stroke patients, the relative change index of M1 beta oscillatory activity under the video AOE condition was significantly lower than that under the observation only and affected hand AOE conditions. Moreover, M1 cortical activity did not significantly differ under the observation only and affected hand AOE conditions. For healthy controls, the relative change index under the video AOE condition was significantly lower than that under the observation only condition. In addition, no significant differences in relative change indices were found under the observation only and video AOE conditions between the 2 groups. This study provides new insight into the neural mechanisms underlying AOE, which supports the use of observing videos of normal movements during action observation therapy in stroke rehabilitation.


Assuntos
Magnetoencefalografia/métodos , Córtex Motor/fisiologia , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/diagnóstico por imagem , Adulto , Ritmo beta/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Movimento/fisiologia , Acidente Vascular Cerebral/fisiopatologia
4.
SLAS Discov ; 23(4): 375-383, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29257918

RESUMO

The endocannabinoid system (ECS) plays a diverse role in human physiology ranging from the regulation of mood and appetite to immune modulation and the response to pain. Drug development that targets the cannabinoid receptors (CB1 and CB2) has been explored; however, success in the clinic has been limited by the psychoactive side effects associated with modulation of the neuronally expressed CB1 that are enriched in the CNS. CB2, however, are expressed in peripheral tissues, primarily in immune cells, and thus development of CB2-selective drugs holds the potential to modulate pain among other indications without eliciting anxiety and other undesirable side effects associated with CB1 activation. As part of a collaborative effort among industry and academic laboratories, we performed a high-throughput screen designed to discover selective agonists or positive allosteric modulators (PAMs) of CB2. Although no CB2 PAMs were identified, 167 CB2 agonists were discovered here, and further characterization of four select compounds revealed two with high selectivity for CB2 versus CB1. These results broaden drug discovery efforts aimed at the ECS and may lead to the development of novel therapies for immune modulation and pain management with improved side effect profiles.


Assuntos
Agonistas de Receptores de Canabinoides/farmacologia , Receptor CB2 de Canabinoide/agonistas , Animais , Células CHO , Cricetulus , Células HEK293 , Ensaios de Triagem em Larga Escala/métodos , Humanos , Dor/tratamento farmacológico , Dor/metabolismo , Receptor CB1 de Canabinoide/agonistas
5.
Mol Biol Cell ; 28(24): 3554-3561, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28954865

RESUMO

G protein-coupled receptors mediate their complex functions through activation of signaling cascades from receptors localized at the cell surface and endosomal compartments. These signaling pathways are modulated by heterotrimeric G proteins and the scaffold proteins beta-arrestin 1 and 2. However, in contrast to the events occurring at the cell surface, our knowledge of the mechanisms controlling signaling from receptors localized at intracellular compartments is still very limited. Here we sought to investigate the intracellular signaling from cannabinoid 2 receptor (CB2R). First, we show that receptor internalization is required for agonist-induced phosphorylation of extracellular signal-regulated protein kinases 1 and 2 (ERK1/2). Then we demonstrate that ERK1/2 activation is mediated by beta-arrestin 1 from receptors localized exclusively at Rab4/5 compartments. Finally, we identify the retromer complex as a gatekeeper, terminating beta-arrestin 1-mediated ERK phosphorylation. These findings extend our understanding of the events controlling signaling from endocytosed receptors and identify the retromer as a modulator of beta-arrestin-mediated signaling from CB2R.


Assuntos
Receptor CB2 de Canabinoide/metabolismo , beta-Arrestina 1/metabolismo , Arrestinas/metabolismo , Canabinoides , Proteínas de Ligação ao GTP/metabolismo , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Fosforilação , Ligação Proteica , Receptor CB2 de Canabinoide/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais/genética , beta-Arrestinas
6.
J Med Chem ; 60(3): 1089-1104, 2017 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-28059509

RESUMO

The allosteric modulator 1-(4-chlorophenyl)-3-(3-(6-(pyrrolidin-1-yl)pyridin-2-yl)phenyl)urea (PSNCBAM-1, 2) bound the cannabinoid receptor 1 (CB1) and antagonized G protein coupling. This compound demonstrated potent anorectic effects similar to the CB1 antagonist rimonabant that once was marketed for the treatment of obesity, suggesting a new chemical entity for the discovery of antiobesity drugs. To increase structural diversity of this class of CB1 ligands, we designed and synthesized two classes of novel analogues, in which the pyridine ring of 2 was replaced by a pyrimidine ring. These positively modulate the binding of the CB1 orthosteric agonist CP55,940 while exhibiting an antagonism of G-protein coupling activity. Interestingly, compounds 7d and 8d demonstrated ERK1/2 phosphorylation mediated via ß-arrestin unlike the orthosteric CP55,940 that does so in a G protein-dependent manner. These can serve as new lead compounds for the future development of CB1 allosteric modulators that show biased agonism and potentially antiobesity behavior via a new mechanism.


Assuntos
Pirimidinas/química , Receptor CB1 de Canabinoide/efeitos dos fármacos , Ureia/análogos & derivados , Regulação Alostérica , Animais , Humanos , Pirimidinas/farmacologia
7.
Pediatr Neurol ; 64: 83-86, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27671242

RESUMO

BACKGROUND: Mitochondrial membrane protein associated neurodegeneration (MPAN) is the third most common subtype of neurodegeneration with brain iron accumulation (NBIA) and caused by mutations of the orphan gene C19ORF12 encoding a transmembrane mitochondrial protein. Like other NBIA disorders, the hallmark of neuropathology is iron deposition in the basal ganglia, but the clinical presentation is highly variable. METHODS: We present the relevant clinical history, neurological examination, electrophysiological and neuroimaging tests of a currently ten-year-old girl. The genetic analysis was carried out by exome sequencing focused on known NBIA and juvenile amyotrophic lateral sclerosis (ALS) genes. RESULTS: The patient presented at four years of age with progressive lower extremity weakness and generalized hypotonia. She was initially diagnosed with juvenile ALS based on clinical signs, negative brain magnetic resonance imaging (MRI) and electromyography findings. As the disease progressed, a repeat brain MRI showed iron deposition in the basal ganglia at nine years of age. Exome sequencing of genes known to be associated with NBIA revealed a compound heterozygous mutation of C19ORF12 gene. CONCLUSIONS: A C19orf12 gene mutation should be considered in young children with clinical signs of progressive upper and lower motor neuron disease. Finding iron accumulation in the basal ganglia helps to focus the genetic testing, but it may not be apparent for several years.


Assuntos
Doenças Neurodegenerativas/diagnóstico , Encéfalo/diagnóstico por imagem , Criança , Diagnóstico Diferencial , Feminino , Humanos , Proteínas Mitocondriais/genética , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/terapia
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